Fig. 7. Three examples of TSR-2s filled with Lucifer Yellow. (A) This example was photographed simultaneously under normal and ultraviolet light. Two dendritic branches from the fusiform receptor cell run anteriorly in contact with the receptor muscle-like strand (dotted lines), and their fine dendritic branches terminate in the neighbouring extensor muscle fibre (small arrows within the rectangle). (B) Two anterior dendrites from a fusiform receptor cell entwine with the muscle strand (asterisks), and a fine dendritic branch on the medial side terminates in the juxtaposed extensor muscle fibre (arrow in the area enclosed by a rectangle and shown in the inset). (C) Fluorescent photomicrograph. The fusiform receptor cell gives off an anteriorly directed stem dendrite, from which a small dendrite entwines with the muscle strand (asterisks) and two dendritic branches bifurcate; one runs towards the neighbouring extensor muscle (arrows) and the other entwines with the muscle strand. In this example, an axon from the posterior pole of the receptor cell can be clearly seen. An, anterior; EMF, extensor muscle fibre; L, lateral; M, medial; P, posterior. Directions in A apply to B and C. All scale bars, 400 µm.
